Domakihub How to Clean a Mortar and Pestle the Right Way
Keep your grinding tool fresh, odour-free, and ready for every recipe.
Reviewed by Domakihub cleaning pros · 2026-06-23 · 4 min read
A mortar and pestle is one of the most useful tools in any Greek kitchen — from crushing garlic and herbs to blending spices for a marinade. But because most mortars are made from porous stone, improper cleaning can leave behind flavours, odours, and even bacteria that ruin your next dish. The video above walks through the visual method; the steps below give you a reliable routine you can follow every single time, whether you run a home kitchen, a holiday rental, or a hotel property.
Why Material Matters Before You Start Cleaning
Granite, volcanic basalt, and unglazed stone are the most common materials for quality mortars, and they are also the most demanding to clean. Their microscopic pores absorb oils, spice compounds, and moisture — which is exactly what makes them so effective at grinding, but also why soap can get trapped inside and taint the next batch of food you prepare.
Ceramic, marble, and glazed porcelain mortars have a non-porous surface, so they tolerate a gentle dish soap wash with no risk of absorption. Knowing your material lets you choose the right method instantly and avoid the most common cleaning mistakes.
The Soap Question: When to Use It and When to Skip It
For unglazed granite or basalt, skip dish soap entirely. These stones soak up detergent, and no amount of rinsing fully removes it — you will taste it for days. Plain warm water, a stiff brush, and a rice grind (explained in Step 3) handle virtually all residue without introducing any foreign flavour.
For glazed ceramic or marble, a small amount of mild, fragrance-free dish soap is perfectly safe. Rinse thoroughly and dry completely before storing. The golden rule: when in doubt, go soap-free and rely on the abrasive power of the stone itself.
How to Clean a Mortar and Pestle: Step by Step
- 1
Scrape out all loose residue immediately after use
While the mortar is still at room temperature, use a stiff brush or a folded piece of paper to remove every visible trace of food — spice powder, herb fibre, garlic skin, oil. The less residue left behind, the easier every subsequent step becomes. Do this while the residue is still dry or barely moist; dried-on food is significantly harder to dislodge.
- 2
Rinse thoroughly with warm water and scrub with a stiff brush
Hold the mortar under warm running water and scrub the entire interior surface with a stiff natural-bristle brush. Pay particular attention to the curved base where oils pool and the rim where fine powder tends to collect. For the pestle, scrub the rounded grinding end in a circular motion. Do not use boiling water on granite, as rapid temperature change can cause hairline cracks over time.
- 3
Grind a tablespoon of dry white rice to purge embedded odours
Add one tablespoon of uncooked white rice to the damp mortar and grind it to a fine powder using the pestle. The rice acts as a gentle mechanical abrasive and absorbs residual oils and odour compounds locked into the stone pores. Discard the powder, then rinse the mortar clean with warm water and repeat with a fresh tablespoon of rice if any odour remains. This rice-grind method is the professional standard for maintaining unglazed stone tools.
- 4
Rinse again and check that the water runs clear and odourless
Do a final thorough rinse under warm running water. Tilt the mortar and watch the run-off — it should be perfectly clear with no colour tinge from spices or oils. Give the interior a quick sniff: you should detect only clean stone. If you still notice a strong spice smell, repeat the rice-grind step once more. A faint mineral scent from the stone itself is completely normal and harmless.
- 5
Dry completely before storing — never store it damp
Turn the mortar upside down on a clean dish rack or folded towel and allow it to air-dry for at least two hours, or place it in a well-ventilated spot. Moisture trapped inside a porous stone mortar encourages mould growth and can cause the stone to crack in cool storage conditions. Once bone dry, store in a cupboard with the pestle resting inside, or wrap the pestle in a clean cloth to protect both surfaces.
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FAQ
- Can I put my mortar and pestle in the dishwasher?
- Only if it is glazed ceramic, stainless steel, or marble — always check the manufacturer's instructions first. Granite, basalt, and unglazed stone must never go in a dishwasher. The intense heat, prolonged moisture, and detergent chemicals will strip any seasoning from the stone, drive soap deep into the pores, and may cause cracking. Stick to the hand-wash method described above for all stone mortars.
- My mortar smells strongly of garlic even after washing. What do I do?
- Garlic oils penetrate deeply into stone. Do two or three consecutive rice-grind cycles, rinsing thoroughly between each one. If the smell persists, grind a small amount of coarse sea salt into the mortar (salt draws out oils), discard, then repeat the rice grind. For extremely stubborn odours, leave the clean, dry mortar outdoors in direct sunlight for a few hours — UV light and fresh air are surprisingly effective at neutralising persistent food smells.
- How often should I deep-clean or re-season a granite mortar?
- A quick clean after every use (Steps 1 and 2 above) is sufficient for day-to-day maintenance. The full rice-grind purge (Steps 3 and 4) is worth doing after processing strongly flavoured ingredients like chilli, garlic, or fish paste, and whenever you notice lingering odours. Re-seasoning — grinding fresh garlic, cumin, or rice repeatedly until the milky stone run-off turns clear — is only needed when the mortar is brand new or has been scrubbed very aggressively and feels rough.